TSR taking much VRAM

[d.cichon]

Hi,

I’m wondering why TSR takes up a lot of VRAM in UE5.5. When rendering in 4K and ScreenPercentage set to 200, it can take up around 1GB of VRAM for graphics resources.

The problem I’m experiencing is a hitch in VRAM when changing the render target resolution (from lower res to 4K), due to TSR taking up so much memory. With the AntiAliasing method switched to None, FXAA or TAA, the resolution change does not result in any VRAM hitches.

I’m sadly not able to reproduce it in a sample project, but in the attached screenshot it’s visible that TSR can take 500MB just for the History.Color information.

Is there a setting/switch/workaround I could try out to mitigate this issue?

Kind regards,

Daniel

[Pjotr]

See this: Temporal Super Resolution Frequently Asked Questions for Unreal Engine | Unreal Engine 5.6 Documentation | Epic Developer Community

Under History Resurrection it says that it needs 2 + “TSR resurrections persistent frame count” (which defaults to 2) so in total 4 buffers, which matches up with your screenshot. With 200 screenpercentage you are making 4 x 8k buffers. This results in the 500mb you see. You can use the cvars in the documentation I linked to reduce the number of buffers or the resolution of the buffers.